https://www.cyberciti.biz/faq/how-to-protect-ssh-with-fail2ban-on-centos-8/
I installed the Centos 8 with minimal options, there is no postfix or sendmail by default.
When I install fail2ban by dnf (yum), postfix is one of the dependent packages.
Now I am done with fail2ban, but I would like to use sendmail instead of postfix, if I run “dnf remove postfix”, fail2ban will be removed too as it is one of dependent packages.
How to remove postfix and install sendmail instead?
Thanks.